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Número de publicaciónUS4966146 A
Tipo de publicaciónConcesión
Número de solicitudUS 07/295,936
Fecha de publicación30 Oct 1990
Fecha de presentación11 Ene 1989
Fecha de prioridad14 Ene 1988
TarifaCaducada
También publicado comoCA1327233C, DE68929007D1, DE68929007T2, EP0324598A2, EP0324598A3, EP0324598B1
Número de publicación07295936, 295936, US 4966146 A, US 4966146A, US-A-4966146, US4966146 A, US4966146A
InventoresStuart C. Webb, Leland M. Lewis, Jayne A. Morris-Thurgood
Cesionario originalWebb Stuart C, Lewis Leland M, Morris Thurgood Jayne A
Exportar citaBiBTeX, EndNote, RefMan
Enlaces externos: USPTO, Cesión de USPTO, Espacenet
Rate-responsive pacemaker
US 4966146 A
Resumen
The slope and threshold of the rate responsive pacemaker are automatically adjustable to suit the physiological requirements of the user.
For threshold adjustment, the user performs a resting level of exertion and the sensor (3) signal is switched (14) to a threshold value generator (15) where its peak value is stored as the threshold value.
For slope adjustment, a target pacing rate is supplied to a store (17) by a programmer (13). The user performs a predetermined constant level of exertion. The resulting pacing rate is compared with the stored target rate in a comparator. The slope is adjusted (16) until the rates are equal. The value of slope is then stored (16).
The sensor (3) may sense any suitable biological variable.
Imágenes(2)
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Reclamaciones(15)
We claim:
1. A pacemaker comprising:
means for producing a first signal indicative of a sensed level of activity of a user,
means responsive to said first signal for producing a second signal as a predetermined function of the first signal to control pacing rate, and
selectively operable means for, when the pacemaker is put in a programming mode, adjusting said function, and comprising:
means for storing a given signal indicative of a particular value of said second signal corresponding to a predetermined level of exercise performed by said user, and
means for varying said function until said second signal is equal to said given signal in response to the first signal produced while the user is performing said predetermined level of exercise.
2. A pacemaker according to claim 1, wherein said varying means is operable, in said programming mode of said pacemaker, for effecting said variation of said function automatically until said second signal assumes said particular value.
3. A pacemaker according to claim 1, wherein said function is linear over a range of values of said first signal, and said varying means effects the varying of said function by varying the slope of said linear function.
4. A pacemaker according to claim 2 or 3, including telemetering receiving means for receiving said signal to be stored in said storing means.
5. A pacemaker according to claim 1, including telemetering receiving means for receiving said signal to be stored in said storing means.
6. A pacemaker according to claim 2, 3, or 5, wherein said function adjusting means adjusts said function so that said pacing rate is not increased above a resting level until said first signal exceeds a threshold.
7. A pacemaker according to claim 1, wherein said function adjusting means adjusts said function so that said pacing rate is not increased above a resting level until said first signal exceeds a threshold.
8. A pacemaker according to claim 7, wherein said function adjusting means includes means for, when the pacemaker is put in said programming mode, setting said threshold, said threshold setting means being operable for sensing variations in said first signal while the user is resting and for selecting the threshold dependent upon said variations.
9. A pacemaker according to claim 8, wherein said threshold setting means is operable to store a peak value of said first signal which occurs during variations thereof while the user is resting and for setting said threshold based on said stored peak value.
10. A pacemaker according to any of claims 1 to 9, wherein said means for producing said first signal comprises a sensor for sensing evokedQt interval.
11. A pacemaker according to any of claims 1 to 9, wherein said means for producing said first signal comprises a sensor for sensing respiratory rate.
12. A pacemaker according to any of claims 1 to 9, wherein said means for producing said first signal comprises a sensor for sensing mixed venous temperature.
13. A pacemaker according to any of claims 1 to 9, wherein said means for producing said first signal comprises a sensor for sensing bodily vibration.
14. A pacemaker comprising:
means for producing a first signal indicative of a sensed level of activity of a user,
means for producing a second signal to control pacing rate and being related to said first signal by a predetermined function such that said second signal changes only in response to said first signal exceeding a threshold, and
selectively operable means for, when the pacemaker is put in a programming mode, varying said threshold, said threshold varying means being operable for sensing variations in said first signal while the user is resting and for selecting the threshold based on said variations.
15. A method of adjusting a rate responsive pacemaker to cause the pacing rate thereof to assume a value required by a user of the pacemaker to perform at a particular level of exertion, the method comprising the steps of:
producing an activity signal representing the level of exertion of the user;
controlling pacing rate to be a predetermined function of said activity signal, said function including a slope component,
producing a first activity signal representing a rest level of exertion of the user,
in a programming mode:
for said activity signal, setting a threshold level based on said first activity signal representing the rest level of exertion so that at said threshold level a transition occurs in the output of said function between a constant pacing rate and a pacing rate which varies with the level of the activity signal,
providing a signal representative of a predetermined value of pacing rate corresponding to a predetermined level of exertion by said user, other than the rest level,
producing a second activity signal representing the said predetermined level of exertion of the user, and
adjusting the slope of said function until the second activity signal representing the said predetermined level of exertion produces via said function a pacing rate representative signal that equals the pacing rate signal representative of the predetermined value of pacing rate.
Descripción

The present invention relates to a cardiac pacemaker.

In the normal healthy individual the output of blood by the heart is varied continuously to meet the metabolic demands of the body The cardiac output changes with variations in the heart rate and the volume of blood pumped at each heart beat The cardiac output is the product of these two variables. During strenuous exercise a four or five fold increase in cardiac output may be required. Approximately 75% of this increase is achieved by elevation of the heart rate.

Patients with cardiac disease resulting in very slow heart rates frequently require treatment in the form of an implanted artificial pacemaker. This consists of a small electrical pulse generator that is connected to the heart by an insulated electrode lead usually positioned in the right ventricle.

Until recently the majority of such pacemakers were relatively simple devices that provided a constant frequency of stimulation. These suffer from the disadvantage that they are unable to increase the heart rate during exercise thereby limiting the degree of exertion that the patient is able to undertake This drawback has led to the development of two forms of pacemaker that can increase stimulation rate during exercise. The "ideal" system is a dual chamber pacemaker which has a second lead implanted in the right atrial chamber of the heart. This detects the rate of the heart's natural pacemaker and enables the artificial pacemaker to provide normal physiological changes in heart rate. However, such systems are not suitable for many patients and also have inherent technical and economic disadvantages.

An alternative approach that has been developed during recent years is the single chamber rate-responsive pacemaker. The fundamental principles of this device are as follows:

(A) A sensor is used to detect changes in a biological variable that are directly or indirectly proportional to the level of metabolic activity in the body. Evoked QT interval, respiratory rate, mixed venous temperature and body vibration are the main variables that are sensed by currently available rate-responsive pacemakers.

(B) The output from the sensor is processed by electronic circuitry to provide a signal that can be used to vary the stimulation rate provided by the pacemaker This circuitry is designed to perform a series of mathematical and logical functions that are known collectively as the rate-response algorithm.

The two principal functions are:

(i) To set the recognition level within the pacemaker for the amplitude of the sensor signal which must be exceeded in order for an increase in pacing rate to be initiated (threshold level).

(ii) To determine the precise mathematical relationship between changes in the sensor signal S and the change in pacing rate R to be provided by the pacemaker, (the slope dR/dS).

Conventional rate response algorithms incorporate a range of values for both the threshold and slope functions These values can be selected by telemetered instructions from an external programmer. The programmer is also used to select the minimum and maximum rates that the pacemaker will generate and to vary a number of other aspects of pacemaker function such as pulse amplitude and duration

The objective of rate-responsive pacing is to provide changes in heart rate that are matched to the varying physiological requirements of individual patients. The conventional programming sequence required to attempt to attain such a match is as follows:

(1) Arbitrary selection of values for threshold and slope.

(2) Clinical evaluation of the resulting rate response Pacing rate must be monitored while the patient is performing different levels of exercise, e.g. at rest and during the performance of an exercise test.

(3) If an inappropriate response is detected, new values for the threshold and/or slope functions have to be selected and the clinical assessment undertaken again.

The latter two steps of the programming sequence may have to be repeated many times before an optimum rate-response is achieved This complex procedure is time consuming and therefore disadvantageous for both the patient and the medical staff involved.

According to an aspect of the present invention, there is provided a rate-responsive pacemaker which is selectively actuable to respond to a sensor signal representing an actual exercise level of a user to automatically adjust the rate-response algorithm in dependence on the sensor signal.

The sensor signal may be produced by any form of biological sensor.

An illustrative embodiment of the pacemaker has provision for adjusting two parameters of the rate-response algorithm. Those parameters are, for example, threshold and slope.

ADJUSTING THRESHOLD

The threshold setting of a rate-response algorithm represents the minimum signal amplitude from the sensor that is required to initiate a increase in pacing rate. Signals below this level will be ignored and under these conditions the pacemaker will continue at its predetermined minimum rate. A practical method in accordance with the embodiment of the invention for selecting an appropriate threshold level for individual patients is to measure the range of variation in amplitude of the incoming sensor signal under resting conditions. Once obtained, this measurement is stored as the threshold value for initiating a rate-response.

The first step in programming the rate-response algorithm of the illustrative embodiment is activation of "Threshold Selection" mode by means of a telemetered instruction from an external programmer.

While "Threshold Selection" is being performed, the patient is kept under resting conditions. The stage last s for some minutes to ensure that an adequate sample of resting signals has been monitored. Programmed deactivation of "Threshold Selection" mod causes the maximum sensor signal measured during this period to be electrically stored within the pacemaker for use by the rate-response algorithm. The stored value may be used as it stands, but it can also be subjected to predetermined increments or decrements to conform to the functional requirements of any different biological sensor system to which it is applied.

Adjusting Slope

It is possible to calculate appropriate "target heart rates" for a rate-response algorithm to achieve under a wide variety of conditions because

(1) Any given form of normal daily exercise (such as walking or climbing stairs) will elicit approximately the same heart rate response in the majority of normal individual subjects.

(2) If an individual subject undertakes progressively increasing levels of exertion (such as a treadmill exercise) then there is an approximately linear relationship between the level of exertion and the increase in heart rate that occurs.

Once the value of the slope required to achieve a suitable heart rate for any given level of exertion has been duly selected, physiologically appropriate rates will be generated at all different exercise levels.

Slope selection circuitry in the illustrative embodiment of the pacemaker automatically varies the slope between preset minimum and maximum limits. The external programmer will be used to give the rate-response algorithm a "Target Rate" that is appropriate to a given level of exertion and at the same time to activate the "Slope Selection" mode The patient then commences the form of exercise chosen for him and after a fixed delay of say two minutes (to allow for physiological equilibration) the incline of the slope is progressively increased from its minimum value to a level at which the pacemaker's rate coincides with the "Target Rate". Once this has occurred "Slope Selection" mode automatically ceases and the value of the slope selected is stored for use in the rate-response algorithm.

By simplifying and automating the setting of the variables for the rate-response algorithm rapidly in each individual implantee this system offers improvements in both functional and economic terms. Furthermore, the likelihood of any operator error occurring may be reduced.

For a better understanding of the present invention, and to show how the same may be carried into effect, reference will now be made by way of example to the accompanying drawings, in which,

FIG. 1 is a graph illustrating the form of a rate-response algorithm, and

FIG. 2 is a schematic block diagram of an illustrative rate-responsive pacemaker according to the present invention.

The illustrative implantable rate-responsive pacemaker shown in FIG. 2 comprises a hermetically sealed can 1 containing a power source 2 (e.g. a battery), an activity sensor 3, a sensor processor 4, circuitry 5 defining a rate-response algorithm, and stimulating circuitry 6. A lead 7 extends from the stimulating circuitry 6 through the wall of the can to a pacing electrode (not shown) for applying an electrical stimulus to the heart of the user of the pacemaker. For simiplicity, the connections from the power source to the various circuits ar not illustrated.

Normal operation of the pacemaker will firstly be described For the purposes of this illustrative description, it is assumed that the sensor 3 senses body vibration although the principles of the present invention can be applied using all forms of biological sensor not just a body vibration sensor.

The activity sensor 3 detects body vibration to produce an activity signal representing the level of exertion of the user. The activity signal is amplified and processed by processor 4 to make the signal more suitable for processing in the circuitry 5.

The circuitry 5 implements the rate-response algorithm; that is the function relating the level of exertion represented by the activity signals to the pacing rate (R) of the pacemaker. As shown in FIG. 1, the algorithm defines a constant pacing rate until the amplitude of the processed activity signal S has a threshold level. The pacing rate R then varies according to a mathematical relationship (e.g. linearly) with the amplitude of the processed activity signal with a slope dR/dS. The pacing rate R has a programmable maximum value (which is not indicated on the graph).

The output of the circuitry 5 is a rate signal representing the pacing rate R appropriate to the user's level of exertion represented by the activity signal S. Stimulation circuitry 6 responds to the rate signal to provide an electrical stimulation to the user's heart via the pacing electrode 7. The lead 7 is a standard unipolar or bipolar transvenous pacing lead. Sensing circuitry 8 is employed to monitor the user's intrinsic cardiac behaviour. If the user's heart beats spontaneously at a rate higher than the pacing rate R, the output of pacemaker stimulation circuitry 6 will be inhibited. The pacemaker will thus function on demand in that it will only stimulate the user's heart to beat if the inherent natural heartrate faIls below the physiologically appropriate rate R.

The activity sensor is shown in FIG. 2 within the can 1. It may be outside the can, being linked thereto via a lead. The sensor may be responsive to stimuli other than body vibration. Examples, as known, include body movement, respiratory rate, evoked QT interval, mixed venous oxygen saturation, right ventricular pressure and/or dimensions, and pH.

In accordance with one aspect of the invention, the threshold value and the slope of the rate-response algorithm are automatically adjustable when the pacemaker is set into a programming mode. In order to set the pacemaker in the programming mode and to provide programming information to the pacemaker, there is provided in the can 1 a telemetry receiver and transmitter 9, a telemetry antenna 10, and a reed switch 11 The receiver and transmitter 9 is inoperative until the reed switch 11 is actuated by an external magnet 12 Once made operative, the receiver 9 can respond to instructions and information transmitted thereto by an external programmer 13 (without use of a physical connection between the receiver and programmer). The transmitter and receiver are for example linked by radio frequency telemetry.

In order to set the threshold value, the programmer 13 causes the receiver 9 to activate switch 14 so that the output of the sensor processor 4 from the circuitry 5 is supplied to a threshold value generator 15. The generator 15 measures the peak amplitude of the processed signal over the period in which the pacemaker is in the "Threshold Select" mode. The peak value is stored in the generator for use either as itstands or in modified form as the threshold value for the algorithm. The modification may be a decrement or increment of the peak value. When the threshold select mode is deselected by the programmer, the switch 14 reconnects circuitry 5 to the processor 4 Whenever the pacemaker is functioning in threshold select mode stimulation circuitry 6 will remain active, providing a pacing stimulus on demand at the programmed minimum rate.

During the Threshold Select mode the user of the pacemaker is kept in a resting condition for several minutes to ensure that the threshold generator 15 samples the rest level activity signal S for an adequate time. The threshold level is thus determined by the actual rest level activity signal produced by the user.

In order to set the slope dR/dS, the programmer 13 causes the receiver 9 to actuate a slope value generator 16, which is initially set to a predetermined initial value of slope. That value could be a minimum value e.g. zero. The programmer also transmits a target value of pacing rate R which is stored in a store 17 The target value is a predetermined value of pacing rate chosen as appropriate to a particular level of exertion of the user.

The user performs the chosen level of exertion. The rate signal representing the pacing rate R produced in response to the resultant activity signal S is compared in a comparator 18 with the target rate in store 17. The value of slope generated by the generator 16 is adjusted until the actual pacing rate equals the target rate.

Upon achievement of equality, the value of slope is stored in generator 16. The adjustment of slope then ends, preferably automatically. The stored value of slope then controls the rate-response algorithm in normal operation of the pacemaker.

The stimulation 6 and sensing 8 circuitry is also capable of being programmed by the external programmer The circuitry 6, 8 is capable of functioning independently of the circuitry 5 to provide a constant demand pacing rate determined by the programmer. One or more of the functional parameters of the circuitry 6, 8 are variable by use of the programmer 13 over a preset range of values.

Those parameters include pulse amplitude and duration, sensitivity, and refractory period.

In a preferred embodiment of the invention the programmer 13 and pacemaker are operable to controI the following modes of operation and parameters:

(a) Mode "Constant Rate", "Rate Response", "Threshold Select" and "Slope Select"

(b) Minimum pacing rate for "Constant Rate" or "Rate Response" modes.

(c) Maximum pacing rate - for "Rate Response" mode only.

(d) "Target Heart Rate" - any chosen value between (b) and (c) above.

(e) Pacemaker stimulation and sensing parameters

(f) Telemetry function - to enable the pacemaker to transmit the values of all programmable parameters out to the external programmer.

Although the principles of automatic slope and threshold selection can be applied to all forms of sensor-modulated rate-responsive pacemakers, the technical details will require a degree of modification in order to conform to the functional requirements of different types of sensor. Thus in the case of respiratory sensing pacemakers, the function of the threshold value generator will be to measure the amplitude of the changes in chest wall impedance that are detected under resting conditions Once this value has been determined, it will be decremented by a preset amount before being stored for subsequent use as the threshold for the rate response algorithm.

Modifications of this sort will be required for each different type of sensor. More extensive changes will be required if the automatic circuitry is incorporated into complex second generation pacing systems with two or more simultaneous sensor inputs, but the same fundamental principles will still apply.

Although an embodiment of the invention has been illustratively described as allowing automatic adjustment of two parameters e.g. slope and threshold other embodiments could allow automatic adjustment of only one parameter, e.g. slope or threshold

Citas de patentes
Patente citada Fecha de presentación Fecha de publicación Solicitante Título
US4273132 *6 Nov 197816 Jun 1981Medtronic, Inc.Digital cardiac pacemaker with threshold margin check
US4340062 *29 Ago 198020 Jul 1982Medtronic, Inc.Body stimulator having selectable stimulation energy levels
US4365633 *22 Feb 198028 Dic 1982Telectronics Pty. Ltd.Patient-operated pacemaker programmer
US4543954 *17 Oct 19831 Oct 1985Purdue Research FoundationExercise responsive cardiac pacemaker
US4550732 *23 Mar 19845 Nov 1985Cordis CorporationSystem and process for enabling a predefined function within an implanted device
US4562840 *23 Mar 19847 Ene 1986Cordis CorporationTelemetry system
US4596251 *10 Oct 198424 Jun 1986Gianni PlicchiMinute ventilation dependent rate responsive pacer
US4719920 *10 Oct 198619 Ene 1988Intermedics, Inc.Exercise-responsive rate-adaptive cardiac pacemaker
US4721110 *24 Jul 198526 Ene 1988Lampadius Michael SRespiration-controlled cardiac pacemaker
US4722342 *16 Jun 19862 Feb 1988Siemens AktiengesellschaftCardiac pacer for pacing a human heart and pacing method
US4763655 *16 Jun 198716 Ago 1988Siemens AktiengesellschaftFrequency-controlled heart pacemaker
US4771780 *15 Ene 198720 Sep 1988Siemens-Pacesetter, Inc.Rate-responsive pacemaker having digital motion sensor
US4782836 *7 Ago 19878 Nov 1988Intermedics, Inc.Rate adaptive cardiac pacemaker responsive to patient activity and temperature
US4807629 *19 Nov 198728 Feb 1989Medtronic, Inc.Oxygen sensing pacemaker
US4817606 *24 Nov 19874 Abr 1989Siemens AktiengesellschaftBody activity controlled heart pacer
US4823797 *15 Jun 198725 Abr 1989Siemens AktiengesellschaftApparatus and method for impedance measurement of body tissues
*DE3419439A Título no disponible
EP0015779A1 *12 Mar 198017 Sep 1980Medtronic, Inc.Apparatus for programming a pacemaker
EP0058603A1 *9 Feb 198225 Ago 1982Medtronic, Inc.Implantable medical device power source depletion indicators
EP0077844A1 *26 Oct 19814 May 1983Vitafin N.V.Pacemaker utilizing microprocessor DMA for generating output pulse sequences
EP0077845A1 *26 Oct 19814 May 1983Vitafin N.V.Programmable cardiac pacemaker
EP0080348A1 *19 Nov 19821 Jun 1983Medtronic, Inc.Rate adaptive pacer
EP0089014A2 *10 Mar 198321 Sep 1983Gianni PlicchiPhysiological implantable cardiac pacemaker in which the stimulation rate is regulated by the respiration rate of the patient
EP0096464A1 *5 May 198321 Dic 1983Purdue Research FoundationExercise responsive cardiac pacemaker
EP0107483A1 *19 Oct 19832 May 1984Medtronic, Inc.Pacemaker programmer with telemetric functions
EP0114679A2 *19 Ene 19841 Ago 1984Telectronics N.V.Cardiac pacer having input/output circuit programmable for use with unipolar and bipolar pacer leads
EP0140472A1 *29 Jun 19848 May 1985Medtronic, Inc.Stroke volume controlled pacer
EP0160801A2 *9 Feb 198213 Nov 1985Medtronic, Inc.Implantable medical device power source depletion indicators
EP0178528A1 *1 Oct 198523 Abr 1986Telectronics N.V.Method for adjusting heart/pacer rate relative to right ventricular systolic pressure to obtain a required cardiac output
EP0191404A1 *4 Feb 198620 Ago 1986Telectronics N.V.Activity sensor for pacemaker control
EP0201990A2 *12 Mar 198620 Nov 1986Intermedics, Inc.Pacemaker with conditional atrial tracking capability
EP0216725A2 *17 Sep 19861 Abr 1987BIOTRONIK Mess- und Therapiegeräte GmbH & Co Ingenieurbüro BerlinPacemaker
EP0222681A1 *17 Sep 198620 May 1987BIOTRONIK Mess- und Therapiegeräte GmbH & Co Ingenieurbüro BerlinHeart pacemaker
EP0249818A1 *4 Jun 198723 Dic 1987Siemens AktiengesellschaftA cardiac pacer for pacing a human heart
EP0249820A1 *4 Jun 198723 Dic 1987Pacesetter ABA cardiac pacer for pacing a human heart
EP0249821A1 *4 Jun 198723 Dic 1987Pacesetter ABA cardiac pacer for pacing a heart
EP0249824A1 *4 Jun 198723 Dic 1987Pacesetter ABA cardiac pacer for pacing a heart
EP0257116A1 *21 Ago 19862 Mar 1988Telectronics N.V.Apparatus and method for adjusting heart/pacer rate relative to ejection time to obtain a required cardiac output
EP0259658A2 *17 Ago 198716 Mar 1988Intermedics Inc.Rate responsive cardiac pacemaker
WO1981001659A1 *10 Dic 198025 Jun 1981American Hospital Supply CorpProgrammable digital cardiac pacer
WO1987001947A1 *6 Oct 19869 Abr 1987Thomas Jefferson UniversityMyocardial contractility-sensitive pacer and method
Otras citas
Referencia
1"Activitrax" Technical Manual-Models 8400/8402/8403.
2 *Activitrax Technical Manual Models 8400/8402/8403.
3Cardiac Pacemaker Regulated by Respiratory Rate and . . . by T. Segura et al., "Pace", vol. 11, Jul. 1988, pp. 1077-1084.
4 *Cardiac Pacemaker Regulated by Respiratory Rate and . . . by T. Segura et al., Pace , vol. 11, Jul. 1988, pp. 1077 1084.
5 *Experience With a Two Sensor Controlled Rate Adaptive Pace Maker System, by H. Heuer et al., vol. 6, No. 2/86, Jun. 1986, pp. 64 67 (Eng. trans.).
6Experience With a Two Sensor Controlled Rate-Adaptive Pace Maker System, by H. Heuer et al., vol. 6, No. 2/86, Jun. 1986, pp. 64-67 (Eng. trans.).
7 *Present State and Future Trends . . . by M. Schaldach, Medical Progress Through Technology, vol. 13, 1987, pp. 85 102.
8Present State and Future Trends . . . by M. Schaldach, Medical Progress Through Technology, vol. 13, 1987, pp. 85-102.
9 *Sensolog 703 Pulse Generator Physician s Manual.
10Sensolog 703 Pulse Generator-Physician's Manual.
11 *Sensor Pacing, Research Leads . . . by Kenneth M. Anderson, Medical Electronics, Oct. 1986, pp. 89 to 93.
12Temperaturgesteurte Schrittmacherstimulation Erste Klinische Ergebnisse, by E. Alt, "Zeitschrift Fur Kardiologie", vol. 74, Settlement 5, Oct. 1985, p. 27.
13 *Temperaturgesteurte Schrittmacherstimulation Erste Klinische Ergebnisse, by E. Alt, Zeitschrift Fur Kardiologie , vol. 74, Settlement 5, Oct. 1985, p. 27.
Citada por
Patente citante Fecha de presentación Fecha de publicación Solicitante Título
US5134997 *14 Ago 19904 Ago 1992Medtronic, Inc.Rate responsive pacemaker and pacing method
US5154170 *14 Ago 199013 Oct 1992Medtronic, Inc.Optimization for rate responsive cardiac pacemaker
US5215084 *16 Jul 19901 Jun 1993BiotronikCardiac pacemaker with activity sensor
US5247930 *4 Feb 199228 Sep 1993Vitatron Medical, B.V.Dual chamber pacing system with dynamic physiological tracking and method of timing delivered stimulus for optimized synchronous pacing
US5271396 *31 Jul 199221 Dic 1993Siemens AktiengesellschaftActivity controlled pacer with automatic sensor response amplification adjustment
US5350409 *19 Abr 199327 Sep 1994Vitatron Medical, B.V.Rate adaptive pacemaker with adjustment of sensor rate as a function of sensed sinus rate
US5423870 *22 Nov 199313 Jun 1995Cardiac Pacemakers, Inc.Rate responsive cardiac pacemaker
US5447524 *25 Jul 19945 Sep 1995Intermedics, Inc.Cardiac pacing method and apparatus responsive to multiple activity types
US5562711 *30 Nov 19948 Oct 1996Medtronic, Inc.Method and apparatus for rate-responsive cardiac pacing
US5620466 *14 Ago 199515 Abr 1997Cardiac Pacemakers, Inc.Digital AGC using separate gain control and threshold templating
US5645574 *29 Nov 19948 Jul 1997Ela Medical S.A.Apparatus and process for control of implantable rate-adaptive cardiac pacemaker
US5658317 *14 Ago 199519 Ago 1997Cardiac Pacemakers, Inc.Threshold templating for digital AGC
US5662688 *14 Ago 19952 Sep 1997Cardiac Pacemakers, Inc.Slow gain control
US5824014 *3 Mar 199720 Oct 1998Biotronik Mess- Und Therapiegeraete Gmbh & Co. Ingenieurburero BerlinMedical therapy device producing a variable therapy in response to measured sensor values corrected with temporal fluctuation values
US6076015 *27 Feb 199813 Jun 2000Cardiac Pacemakers, Inc.Rate adaptive cardiac rhythm management device using transthoracic impedance
US6161042 *21 May 199912 Dic 2000Cardiac Pacemakers, Inc.Rate adaptive cardiac rhythm management device using transthoracic impedance
US6282446 *24 Ago 199928 Ago 2001Cardiac Pacemakers, Inc.Automatic shock lead gain adjuster
US646332620 Ene 20008 Oct 2002Cardiac Pacemakers, Inc.Rate adaptive cardiac rhythm management device using transthoracic impedance
US65911369 Jul 20018 Jul 2003Cardiac Pacemakers, Inc.Automatic shock lead gain adjuster
US666204917 Dic 19979 Dic 2003Pacesetter, Inc.Implantable device with a programmable reset mode and method of operation
US67788559 Jul 200117 Ago 2004Cardiac Pacemakers, Inc.Automatic shock lead gain adjuster
US683420520 Ene 200421 Dic 2004Cardiac Pacemakers, Inc.Automatic shock lead gain adjuster
US68538605 Mar 20038 Feb 2005Cardiac Pacemakers, Inc.Automatic shock lead gain adjuster
US6859765 *13 Dic 200222 Feb 2005Lam Research CorporationMethod and apparatus for slope to threshold conversion for process state monitoring and endpoint detection
US70623266 Feb 200313 Jun 2006Cardiac Pacemakers, Inc.Method and apparatuses for monitoring hemodynamic activities using an intracardiac impedance-derived parameter
US709275712 Jul 200215 Ago 2006Cardiac Pacemakers, Inc.Minute ventilation sensor with dynamically adjusted excitation current
US710133913 Dic 20025 Sep 2006Cardiac Pacemakers, Inc.Respiration signal measurement apparatus, systems, and methods
US72004402 Jul 20033 Abr 2007Cardiac Pacemakers, Inc.Cardiac cycle synchronized sampling of impedance signal
US77749348 Dic 200517 Ago 2010Cardiac Pacemakers, Inc.Method for making a terminal connector
US805076429 Oct 20031 Nov 2011Cardiac Pacemakers, Inc.Cross-checking of transthoracic impedance and acceleration signals
US820901117 Sep 200726 Jun 2012Cardiac Pacemakers, Inc.Automatically configurable minute ventilation sensor
US820903523 Jun 200826 Jun 2012Cardiac Pacemakers, Inc.Extendable and retractable lead having a snap-fit terminal connector
US82853987 Jul 20109 Oct 2012Cardiac Pacemakers, Inc.Lead with terminal connector assembly
US830662116 Feb 20076 Nov 2012Cardiac Pacemakers, Inc.Cardiac cycle synchronized sampling of impedance signal
US842314231 Oct 201116 Abr 2013Cardiac Pacemakers, Inc.Cross-checking of transthoracic impedance and acceleration signals
US8433396 *18 Abr 200330 Abr 2013Medtronic, Inc.Methods and apparatus for atrioventricular search
US844263330 Oct 201214 May 2013Cardiac Pacemakers, Inc.Cardiac cycle synchronized sampling of impedance signal
US868821410 May 20131 Abr 2014Cardiac Pacemakers. Inc.Cardiac cycle synchronized sampling of impedance signal
US888017113 Feb 20144 Nov 2014Cardiac Pacemakers, Inc.Cardiac cycle synchronized sampling of impedance signal
US960406330 Oct 200628 Mar 2017Medtronic, Inc.Method, apparatus and system to identify optimal pacing parameters using sensor data
US20030105499 *8 Oct 20025 Jun 2003Cardiac Pacemakers, Inc.Rate adaptive cardiac rhythm management device using transthoracic impedance
US20030114889 *6 Feb 200319 Jun 2003Cardiac Pacemakers, Inc.Method and apparatuses for monitoring hemodynamic activities using an intracardiac impedance-derived parameter
US20040117054 *13 Dic 200217 Jun 2004Lam Research CorporationMethod and apparatus for slope to threshold conversion for process state monitoring and endpoint detection
US20040147970 *20 Ene 200429 Jul 2004Cardiac Pacemakers, Inc.Automatic shock lead gain adjuster
US20040215262 *18 Abr 200328 Oct 2004Bozidar Ferek-PetricMethods and apparatus for atrioventricular search
US20050004610 *2 Jul 20036 Ene 2005Jaeho KimCardiac cycle synchronized sampling of impedance signal
US20080103539 *30 Oct 20061 May 2008Berthold StegemannMethod, Apparatus and System to Identify Optimal Pacing Parameters Using Sensor Data
EP0528224A1 *29 Jul 199224 Feb 1993Pacesetter ABSensor-controlled implantable medical device
Clasificaciones
Clasificación de EE.UU.607/19, 607/20, 607/22, 607/23, 607/31, 607/25
Clasificación internacionalA61N1/372, A61N1/365
Clasificación cooperativaA61N1/37252, A61N1/36514
Clasificación europeaA61N1/365B
Eventos legales
FechaCódigoEventoDescripción
11 Abr 1994FPAYFee payment
Year of fee payment: 4
27 Mar 1998FPAYFee payment
Year of fee payment: 8
14 May 2002REMIMaintenance fee reminder mailed
30 Oct 2002LAPSLapse for failure to pay maintenance fees
24 Dic 2002FPExpired due to failure to pay maintenance fee
Effective date: 20021030